Since the 1980s, several unconventional superconductors have been discovered, some of which exhibit triplet pairing (total spin S=1) that may lead to interesting topological properties. Unlike singlet superconductors, their order parameter is a vector depending on the spin components (S_z=-1,0,1) and is strongly influenced by the crystal symmetry and the spin–orbit coupling (SO).
The thesis aims to study the transition between weak and strong spin–orbit coupling in a triplet superconductor, using a minimal multiband model inspired by the material CdRh2As3, where a field-induced triplet phase was recently observed. This research will enable the calculation of the dynamic spin susceptibility and the identification of possible collective spin resonances, similar to those seen in superfluid He3.
The project will mainly rely on analytical field-theoretical methods applied to condensed matter. It is intended for candidates with a solid background in quantum mechanics, statistical physics, and solid-state physics.